As Britain prepares to celebrate the 90th anniversary of the Royal Air Force, Germany is reclaiming the First World War flying ace known as the Red Baron as a national hero.

On Tuesday, Henry Allingham, 111, the oldest British survivor of the war, will join guests at a commemorative dinner at the RAF Museum in Hendon, north London. On 1 April, the RAF will mark the service's birthday with a spectacular aerial display over London. Then a week later, the controversial film The Red Baron will have its premiere in Germany, with a UK release to follow.

In Germany, where painful milestones of war often pass without ceremony, £14m has been spent on the new film about the country's most famous fighter pilot, Manfred von Richthofen, making it one of the most expensive in the country's history. The Red Baron, who shot down 80 British, Canadian and Australian pilots, is portrayed as a brilliant and sensitive hero in the English-language production.

The film has been described as breaking a taboo which for decades has seen German soldiers generally portrayed as callous zealots or conscripts tormented by conscience. But there has been renewed appetite for exploring the country's wartime past since the release of Downfall in 2004, and later this year Tom Cruise plays Claus von Stauffenberg, the German colonel who tried to assassinate Hitler, in Valkyrie

Nikolai Müllerschön, writer and director of The Red Baron, said: 'Historically there has been a reluctance, and there are strong voices in Germany still saying we're not allowed to do this: a film about a German war hero. But the film makes a very clear statement against war. In it Richthofen says that he understands everyone has turned this world into a slaughterhouse and the war cannot be won. He says he's not going to be the immortal god that Berlin wants him to be; he knew millions were lured into the trenches with such propaganda. He had been turned into one of the first pop stars in history by one of the biggest propaganda machines ever seen.'

The Red Baron casts rising star Matthias Schweighöfer as Richthofen and two British actors in key roles. Joseph Fiennes, star of Shakespeare in Love and Enemy at the Gates, plays Captain Roy Brown, a Canadian initially hailed as the Red Baron's conqueror, a claim he never made and later discredited. Lena Headey, best known for 300 and television's Terminator: The Sarah Connor Chronicles, is the love interest Käte Otersdorf, a nurse who may or may not have had a romance with Richthofen in real life.

Richthofen was 25 when he was killed in combat near the Somme at noon on 21 April 1918, but the exact cause has been debated ever since. Peter Kilduff, who has written six books about the Red Baron, recently made a potentially dramatic discovery when he bought a 1932 German veterans magazine on the auction website eBay. Buried inside was an article entitled 'The Truth About Richthofen's Death - Eyewitness Account by Hermann Bink'. Kilduff translated it into English and found the allegation that Richthofen survived a crash landing only to be stabbed by watching soldiers.

Bink was quoted: 'It is possible that the engine of Richthofen's airplane was hit and perhaps he was as well. But in any event, we saw him climb out of the airplane alive! Several brown forms fell on him with drawn daggers and presumably stabbed him. They were British colonial troops, which were opposite us.'

The magazine quoted other supposed eyewitnesses in support of Bink. But Kilduff, whose book Red Baron: Life and Death of an Ace, rejects the claims. Instead he backs the view of historian and retired cardiologist Geoffrey Miller, who believes the Red Baron was probably brought down by Sergeant Cedric Popkin, an Australian machine gunner. The angle of the entrance and exit wounds on Richthofen's body indicates that he was hit as he was trying to turn away from Popkin's fire. Miller said: 'There is little doubt that the bullet penetrated his heart and was fatal.'

The RAF - an amalgamation of the Royal Naval Air Service, to which Henry Allingham belonged, and the army's Royal Flying Corps - will hold a series of events including a commemorative service at St Clement Danes Church in London and a concert in Birmingham. It will issue service badges to 25 veterans and, most spectacularly on 1 April, stage an aerial display by the Red Arrows above central London culminating at the London Eye.